A method of treating bovine mastitis by means of an erythromycin solution

ABSTRACT

A method of treating bovine mastitis by injecting through the teat orifice of an infected quarter a solution of erythromycin in a fatty acid triglyceride having an iodine value of less than 42. This method, by virtue of the unique solution offers not only effective mastitis control, but also the distinct advantage of a shorter period of detactable drug residue in the milk than heretofore obtainable. Milk taken after the third milking following the last treatment is free from detectable erythromycin residue.

United States Patent 1191 Banford [4 1 Dec. 25, 1973 [54] A METHOD OF TREATING BOVINE MASTITIS BY MEANS OF AN ERYTHROMYCIN SOLUTION [75] Inventor: John Alexander Banford, Lake, "L

[73] Assignee: Abbott Laboratories, North Chicago, Ill.

[22] Filed: Mar. 9, 1971 [21] Appl. No.: 122,499

Related US. Application Data [63] Continuation-impart of Ser. Nos. 562,107, July 1, 1966, abandoned, and Ser. No Continuation of Ser. No. 720,452, April 11, 1968, abandoned.

[52] US. Cl. 128/260, 424/181 [51] Int. Cl A61m 31/00 [58] Field of Search 424/181; 128/260 [56] References Cited UNITED STATES PATENTS 3,013,941 12/1961 Gunderson 424/181 3,135,658 6 1964 1146115 et al 424/181 3,144,386 8 1964 Brightenback 24/181 3,347,743 10 1967 Reuter et al. 424/181 1 Primary Examiner-Albert T. Meyers Assistant Examiner-Daren M. Stephens Attorney-Robert L, 'Niblack [57 ABSTRACT 4 Claims, No Drawings A METHOD OF TREATING BOVINE MASTITIS BY MEANSOF AN ERYTHROMYCIN SOLUTION This is a continuation-impart of Ser. No. 562,107 filed July 1, 1966 now abandoned; and continuation of my pending application, Ser. No. 720,452, filed Apr. 1 l, 1968 and now abandoned.

This invention relates to a method for treating infectious bovine mastitis with a medicinal preparation containing erythromycin base. More particularly, this invention relates to the administration of stabilized erythromycin base solution into the infected area by injection through the teat orifice of an infected udder quarter.

The mode of treatment of the present invention is especially effective against the causative organisms of more than 90 percent of the infections caused by Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalacliae, and Streptococcus uberis. It has further been found that the method of this invention is effective in eliminating both the clinical signs and the pathogenic bacteria associated with mastitis caused by the above organisms. It should nevertheless be understood that infectious mastitis, as that term is used herein, is meant to describe non-specific infections causing inflammation of the mammary tissue in bovine species. To that end infections, especially grampositive bacterial infections, caused by organisms susceptible to erythromycin can be treated by the method of this invention. Furthermore, when the method of this invention is practiced, less than of the total dose of erythromycin is recovered in excreted milk. As shall be seen later this is because the erythromycin is absorbed into the mammary tissue. This is especially important since Staphlococcus organisms tend to infect the interstitial mammary tissue. Unless there is good absorption, the site of infection will not be reached.

Hence, one of the primary objects of this invention is to provide a method for treating infectious mastitis that does not require disposing as waste that milk excreted long after treatment. Regulations provide that milk contaminated with any antibiotic shall not be used for human consumption. With prior modes of treatment, milk taken as long as 96 hours following the last installation of drug contained sufficient antibiotic to require discarding that milk.

Now it has been found that by practicing the method of this invention, there is provided milk free from drug residue within 36 hours following the last installation. Indeed this is contrary to prior art teachings that a long residue pattern, i.e., protracted appearance of residual antibiotic, was requisite to proper therapy.

The composition of the medicinal preparation used in practicing the method of this invention is erythromycin base dissolved in a fatty acid triglyceride that is liquid at the temperature of anticipated use. Erythromycin base refers to that form of erythromycin where the amino nitrogen atoms are not protonated, as opposed to the so called acid-addition salt forms of erythromycin. The stability of erythromycin base is required both during storage and use. It has been found that the stability decreases as the degree of fatty acid unsaturation increases. This makes it necessary to select a fatty acid triglyceride so that the fatty acid is sufficiently saturated to yield a stabilized solution. It has further been found that if the fatty acid triglyceride has an iodine value less than 42, a sufficient and desirable degree of stability is attained.

Most satisfactory are those fatty acid triglycerides wherein each of the fatty acid moities has from 8 to about 10 carbon atoms and the iodine value is less than The preferred'solution comprises partially hydrogenated coconut oil,'having an iodine value within the previously specified limitation. Such an oil is sold under the trademark Neobee M-5 by Drew Chemical Company, New York, NY.

The erythromycin base is dissolved in the oil at a concentration of from about 10 to about 200 mg/ml of solution.

These homogenous solutions are not only more stable than other solvents or suspending agents for erythromycin base, but have the further advantage that they can be filtered to free them from bacteria. This yields an essentially sterile product.

If desired, one can add small amounts of antioxidants to achieve even increased stability. A preferred solution consists of the following.

This amount of solution after sterilization if desired can be packaged in a disposable syringe. Thus, a single dose will comprise 300 mg of erythromycin. While this dose is preferred, a dosage of from -500 mg of erythromycin is effective and well tolerated.

The method of administering the medicinal preparation of this invention will now be described.

Each infected quarter of an udder into which one intends to install the medicinal preparation is thoroughly milked out. The udder and teats are then cleaned by conventional washing techniques. Each of teat orifice into which installation is to be accomplished is disinfected preferably by swabbing with cotton soaked in ethanol or other suitable disinfectant. So as to avoid recontamination it is suggested that the teats farthest from the operator be disinfected first.

Then a suitable container such as a syringe or tube nozzle containing the hereinbefore described stable and sterile medicinal preparation is inserted into the teat orifice, starting with those nearest the operator if more than one quarter is to be treated. The contents of the container are infused into the infected quarter. The nozzle or syringe of the container is then removed and the teat orifice gently closed and the udder massaged to distribute the medicinal preparation.

When lactating cows are treated, it is preferred that the treatment be repeated following three consecutive milkings.

It has been found, as reported in Table I, that relatively high concentrations of erythromycin occur in udder tissue following the intramammary infusion of a 1200 mg dose to normal lactating dairy cows. It is particularly interesting to note that drug distribution occurred fairly uniformly between front and rear quarters and throughout the upper portion, as well as the lower third of the glands. The udder tissue fluid samples, re-

.ferred to in Table l, are considered to be derived primarily from fluids collected fromt the duct system. These data indicate erythromycin distributes rapidly and uniformly throughout the milk duct system.

. TABLE I Erythromycin Concentration in Bovine Milk and Udder Tissue (meg/ml of Fluid or meg/gm of Wet Tissue) Udder Tissue Fluid Drained Udder Tissue Sample Period Cow Milk Upper 113 Lower 113 Upper l/3 Lower 1/3 Front Rear Front Rear Front Rear Front Rear Pre-lnfusion: 89 .0146 .022 .022 .022 .022 .135 .135 .135 .135 Post Infusion:

2 hours 91 185.0000 79.000 10.500 53.200 41.200 34.600 23.800 26.200 34.300

6 hours 74 306.0000 .857 1.750 12.900 23.700 .917 .958 3.670 14.300 l2 hours 130 21.7000 .185 .430 2.500 2.850 .170 .175 1.530 3.300

24 hours 136 .0550 .020 .020 .031 .020 .135 .135 .135 .l35

' Therapid rate of absorption of erythroinycin 1315651 served for erythromycin follows kinetic principles of critically demonstrated in Table 11, where relatively absorption, distribution and excretion. high levels were observed at 2 hours in serum, liver, The duration of residue was found to be short for all bile, kidney and urine. tissues. Milk and one udder tissue sample exhibited the TABLE II I Erythromycin Concentration in Bovine Fluids, Tissues and Feces (mcglml Fluid or mcdgm of Wet Tissue) Cow Udder Sample Penod No. Lymph Blood Liver Bile Kidney Urine Muscle Fat Feces Pre-lnlusion: 89 .050 .03l .160 4.00 .100 .75 .20 .10 .50 Post Infusion:

Zhoun 91 9.670 .100 .917 4.28 .542 3.40 10 50 fihours 74 5.830 .177 2.030 5.40 1.040 10.30 20 .10 3.40

12 hours 130 .642 .031 .202 4.00 .1110 3.51 20 .10 2.05

' 'lt was fiiund that erytlirornycin is not only dispersed last detectable residue at 24 hours. All other tissues in the gland duct system and absorbed into the local were negative at 24 hours. it is of interest that no levels udder tissue, but broad distribution throughout other were detected in muscle, the primary edible tissue body tissues and fluids occurred. This distribution patther than milk, at any sampling period. tern is similar to that following parenteral administration.

7 Tables 11, lll and lV illustrate the residue in milk. It will be seen that there is virtually no residue in the milk taken 36 hours,that is the third milking following the last infusion of the erythromycin base solution.

It was observed that the highest levels in the local udder tissues occurred at the 2 hour sampling period, 40 whereas the highest levels for blood, liver, bile, kidney, fat, and urine occured at the 6 hour sample period. The pattern of drug residue in the feces is particulary noteworthy since no level was detected at 2 hours, the peak in Tabled [lithe ave rage residue foi anim als treated level occurred at 6 hours, and a somewhat lower level according to this invention at three dosage levels is set found at 12 hours. This general distribution pattern obforth.

7 TABLE 111 ERYTHROMYC IN MILK RESIDUES Mean Erythromycin Cone. (meg/ml) Dosage 7' Number of H Number of 12 hrs 12 hrs 1105 051155115051:

Animals Quarters Post Post 1st 2nd 12 hrs 24 hrs 36 hrs Dose Dose Per infusion (4) (2) Figures in parenthesis indicate number of animals exhibiting detectable levels of antibiotic.

Table IV illustrates the residue pattern for individual animals.

Table V shows th dfig residue after the third milking at differing intervals.

TABLE IV ERYTI-IROMYCIN MILK RESIDUES Animal to Animal Variation Erythromycin Concentration (mcglml) Animal No. of No. of 1st Milking 1st Milking No. of Milking Post Last Dose No. Studies Quarters Post Post 1st Dose 2nd Dose 1st 2nd 3rd 4th 5th Milking Milking Milking Milking Milking Trace level detected below sensitivity of analytical method. Figures in r V of exhibiting erythromycin levels.

TABLE V ERYTHROMYCIN MILK RESIDUES Sampling Time Effect Erythromycin Dosage 300 mglquaner Erythromycin Concentration meg/mg Sampling No. of No. of 1st Milking lst Milking No. of Milkings Post Last Dose Sequence Animals Quarters Post Post 1st Dose 2nd Dose 1st 2nd 3rd 4th 5th Milking Milking Milking Milking Milking and9Hr. 7A 7 v, W

Intervals 6 10 4.00 21.91 3.06 0.17 0.00

Intervals 11 44 13.39 15.45 5.09 0.28 0.02

1) (l l) 9 and 15 Hr.

Intervals 7 22 65.16 13.95 69.85 0.45 0.00

Trace level detected below sensitivity of analytical method.

Figures in parenthesis indicate number of animals exhibiting detectable residue levels of erythromycin.

I claim:

1. A method of treating infectious bovine mastitis comprising the steps of milking a bovine host. injecting an infusion means into the teat orifice of an infecte d udder quarter, transferring a sterile stable homogenous medicinal preparation from said infusion means into the udder interior; said preparation comprising 100 500 mg of erythromycin base dissolved at a concentra- U'NITED STATES PATENT. OFFICE CERTIFICATE OF CORRECTION Patent No. 3,7 0,737 Dated December 25, 1973 Inventor-(s) John Alexander Banford It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, following line- 23, please insert:

"Erythromycin Base 300 mg Butylated Hydroxy Anisole 0.45 mg Butylated Hydroxytoluene 0.45 mg Sufficient Neobee M-S to produce 6.00 ml of solution" Column 4, TableiIII, under the heading"'Dosage": Line 1, please delete "100" and substitute therefor "200" Line 4, please delete 100" and substitute therefor "300" Signed and sealed this 9th day of July 1974.

(SEAL) Attest:

MCCOY M. GIBSON, JR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents FORM PC 0 p I uscoMu-oc scan-Poo IL. GQUIIIIINY PIIIYING O'HCI If, O-Ji-Sl 

2. A method according to claim 1 in which said milking infusion and massage steps are repeated for three consecutive milkings.
 3. A method according to claim 1 in which said fatty acid triglyceride has an iodine number less than 5 and said fatty acid moities each have from 8-10 carbon atoms.
 4. A method according to claim 1 in which said fatty acid triglyceride is a partially hydrogenated coconut oil. 